1. Field of the Invention
The present invention relates to a ventilation structure of a cover for a disk drive, more particularly to a ventilation structure of a cover for a magnetic disk drive designed so that air can circulate between the inside and outside of the disk drive.
2. Description of the Related Art
In recent years, magnetic disk drives, optical disk drives, and other disk drives have been used as storage devices for computers. These disk drives are used in various environments together with the computers. Accordingly, when leaving a disk drive in a general environment in a nonoperating state, there is the risk that the passage of air between the inside and outside of the enclosure of the disk drive, comprised of a cover and base, will lead to the entry of harmful sulfur, sulfur dioxides, and the like to the inside of the disk drive (the entry of molecules of gas due to diffusion).
Therefore, in the past, a ventilation structure (breather structure) for preventing the entry of harmful gas into the disk drive by providing the cover of the disk drive with a gas adsorption filter has been proposed. The conventional ventilation structure provided for the cover of a disk drive, however, has been complicated in construction and high in cost, so a ventilation structure of a simpler configuration and lower cost has been desired.
For example, U.S. Re. Pat. Nos. 34,497 and 5,030,260 disclose conventional disk drives providing ventilation structures at their housings or covers, but since the ventilation members with the ventilation grooves are made by separate members from the housings and covers, work has been required for assembling these separate members with the covers etc. Considering the cost of fabricating the separate members themselves, further, there is the problem that the cost of manufacturing the disk drives becomes higher.